The present invention relates to an optical sensor device that can be installed on board a motor vehicle and that can be used as an aid to driving and/or for automatic activation of on-board systems of the motor vehicle.
In particular, the invention regards an optical sensor device of the type comprising:                an optical sensor in the form of a CCD or CMOS array, having a sensitive area in which a number of sub-areas is defined, each of which is designed for a specific optical function corresponding to monitoring of the scene in front of the motor vehicle and/or to detection of environmental parameters; and        a plurality of optical systems with different directions of the optical axis and/or fields of vision, designed to send optical signals to respective sub-areas of the sensitive area of said array, for the purpose of performing the aforesaid functions,        
in which at least some of said sub-areas are defined by different and separate portions of the sensitive area of said array dedicated to different optical functions, and
in which said different and separate portions of the sensitive area of the array include at least:                a first portion of the top part of the sensitive area, defining a first sub-area, for detection of fog in front of the motor vehicle;        a second and different portion of the sensitive area, defining a second sub-area, for detection of a twilight condition;        a bottom portion of the sensitive area, defining a third sub-area, separate from said first and said second sub-areas, for monitoring the scene in front of the motor vehicle;        a further portion of the top part of the sensitive area, defining a fourth sub-area different and separate from the first, second and third sub-areas, for detecting the presence of raindrops or of mist on the windscreen or on the rear window of the motor vehicle;        a first optical system for conveying optical signals on said first sub-area for detection of fog, including a light emitter for emitting light in the direction of the space in front of the motor vehicle, a receiver for receiving light scattered by the fog possibly present in front of the motor vehicle, and optical means for directing the light received only on said first sub-area of the sensitive area of said array; and        a second optical system, a third optical system, and a fourth optical system, provided for directing optical signals on said second, third and fourth sub-areas of the sensitive area of said array, respectively for detection of a twilight condition, for monitoring of the scene in front of the motor vehicle, with particular reference to a condition in which the vehicle crosses another vehicle coming in the opposite direction or to a condition of passing through a tunnel, and for detection of raindrops or of mist on the window of the motor vehicle.        
A sensor device having all the aforesaid characteristics has formed the subject of the European patent application No. EP 1 418 089 A2, filed in the name of the present applicant.